The objective of the proposed research is to define the mechanism of action of the important nutritional component vitamin A at the molecular level in organs other than the eye. Emphasis is given to investigation of possible alterations in the transcriptional mechanism during vitamin A deficiency and refeeding. Efforts will be made to purify and characterize the specific cytoplasmic binding protein for retinol (Vitamin A) discovered recently by this laboratory to be present in a number of organs in all species examined and to delineate its role in cell metabolism. The levels of the binding protein will be examined during perinatal development of the rat. Special attention will be given to the influence of nutrition of the mother on the content of this protein in the child. Nutritional and biochemical studies are emphasized.